1. Field of the Invention
This invention relates to an assembly for mounting electrical apparatus such as transformers or the like upon a utility pole, wherein the assembly includes a number of mounting brackets that are each adapted to support the apparatus as well as elongated members or plates that extend between the brackets and which have toothed end regions for enabling adjustment of the size of the assembly in accordance with the diameter of the selected utility pole. More particularly, the invention concerns a locking spring which is fixed to the bracket adjacent an L-shaped aperture in the bracket for retaining one of the toothed end regions of a plate partially within the confines of a narrower leg of the aperture, thereby preventing unintentional withdrawal of the plate from the aperture during installation of the assembly upon a utility pole.
2. Description of the Prior Art
Mounting devices for supporting electrical apparatus such as transformers and related equipment on a pole often include means for carrying one, two or three transformers at spaced locations around the periphery of the pole. Since the diameter of wooden utility poles may vary considerably from pole to pole, it is important that mounting devices or assemblies which extend around the circumference of the pole be adjustable in order to vary the size of the assembly to compensate for the diameter of the particular, selected pole. It is also desirable to construct such mounting assemblies from extruded aluminum components that are easy to assemble to a rigid, interlocking configuration and that are relatively light in weight so that the weight of the assembly and the equipment mounted thereon is minimized.
In the past, certain mounting assemblies which surround the pole and support a cluster of electrical devices such as transformers have been provided with a plurality of mounting brackets each adapted to support one of the transformers, as well as toothed members or plates which span the distance between adjacent brackets in order to mechanically interconnect the latter and retain the brackets in secure, fixed engagement with the pole. During assembly of the mount, the size or effective internal diameter of the mount may be varied to accommodate the diameter of the pole by longitudinally and laterally shifting one or more of the toothed plates relative to the corresponding brackets to enable a particular selected tooth of the plate to come into contact with the bracket. One example of this type of construction is shown in U.S. Pat. No. 3,374,978 dated Mar. 26, 1968.
The brackets which receive the toothed, interconnecting plates of prior art transformer mounting assemblies such as the type shown in U.S. Pat. No. 3,374,978 have apertures which are of a generally rectangular configuration that is complemental in configuration and slightly larger than the overall rectangular shape of the toothed region of the plate, so that the latter can be readily inserted into the aperture during assembly of the mount. U.S. Pat. No. 3,497,171 illustrates the provision of a separate retaining clip which is inserted behind the plate in the aperture once the plate is moved to a position causing one of the teeth to engage a marginal edge portion of structure defining the aperture, in order to reduce the likelihood of accidental disengagement of the selected tooth from the edge portion and withdrawal of the plate from the aperture of the bracket. Such clips are useful for maintaining the transformer mount in an assembled configuration during installation; once the assembly is mounted upon a pole and adjusting bolts are tightened to draw the mount into firm, surrounding contact with the pole, the teeth, being slightly inclined, subsequently remain in fixed, seating engagement with marginal edge portions of the brackets surrounding the aperture.
Unfortunately, a number of disadvantages have been associated with clips of the type illustrated in the aforementioned U.S. Pat. No. 3,497,171. For example, such clips are separate components which may be lost, or alternatively the linesmen may simply forget to install the clip in place. In addition, two hands are necessary for installing such clips, as the toothed regions of the plate must be maintained in proper disposition while the clip is inserted in the space between one side of the plate and a marginal edge of the bracket defining the aperture. Problems of this nature are somewhat compounded by the fact that the work is often undertaken in the field where suitable work surfaces are not available.